The former president is the latest person close to George W. Bush -- the former Texas governor -- to back Hutchison, joining Karl Rove, Karen Hughes, and Dick Cheney.

The primary is March 2, which happens to be Texas Independence Day. Perry is viewed as the favorite in the contest.

Per a release from the Hutchison campaign, "Barbara and I are taking this unusual step of endorsing in this primary because of our unbridled belief in Kay. She is strong. She has proven her steadfast commitment to the issues and values that unite Texas Republicans. And we are proud to stand with her today," said former President Bush.

More: "Kay is a respected national leader on many of the same issues that Texas is confronting today. These are tough, complex issues, but we have every confidence that Kay can get positive action after years of drift and delay.

And: "This election is about the future, not the past - and we have no doubt that Kay has the right vision and values to help Texas build an even better tomorrow."